RIPP has relied on NGK spark plugs for over 20 years because of their high quality and reliability. Most RIPP kits come with two variants of NGK spark plugs, V-Power and Iridium. The WK Iridium spark plugs deliver the spark serious enthusiasts rely on. Designed specifically for the performance enthusiast. Iridium IX offers extreme ignitability, improved throttle response and superior anti fouling.